Many traditional acoustic musical instruments, such as percussion instruments, cannot be easily emulated or synthesized by electronic systems. While attempts have been made to build electronic drums, such electronic drums do not currently reproduce the sound of acoustic drum kits, and the subtlety of an acoustic performance may be lost by using existing electronic equivalents of drums.
Modern electronic drum kits are typically activated using a set of binary triggers, such that striking an electronic drum pad at a trigger will produce a specific sound. However, an acoustic drum kit can produce a much wider variety of sounds by using the main drum pad as a continuum, rather than a series of discrete triggers, using the rim of the drum as part of the instrument, and by striking a drum with different materials or utilizing different techniques, each activating the acoustics of the physical object in different ways to produce different sounds. For example, drummers may make unique sounds by hitting the rim of a drum or a side of a drum, or other locations where electronic devices may not have triggers. While some electronic drum pads can distinguish between harder and softer hits, they are still limited to which trigger is activated and at what force.
Traditionally, acoustic drum sounds have been captured by standard acoustic microphones that are prone to also detecting ambient sounds other than those emanating from the drums. Such ambient sounds may include unwanted sounds that are difficult to isolate during processing. Further, such microphones may create signals that are usable to recreate the specific audio from the performance captured, but which cannot be used to modify or refine playback of the performance, since such signals are difficult or impossible for a computerized system to interpret. Further, such signals cannot be easily used to control a computer and cause customized playback of audio other than an amplified version of that captured.
Further, existing electronic drum kits require musicians to familiarize themselves with a new set of equipment that looks and feels different from what they are used to. Drummers are typically comfortable with their kit, and they are proficient at executing special drumming techniques on the equipment they have used for years.
The key issue is one of human-computer interaction. Currently, computer interfaces for musicians typically require the use of binary buttons, knobs and controls of limited dimensionality. To use a computer for musical creation requires that you learn the interfaces of the system. Since these interfaces are typically composed of low dimensional input devices, the range of musical expressivity inevitably falls short of what is possible with acoustic instruments. Unlike computer interfaces, acoustic instruments have extraordinarily complex analog interfaces. Take for example a drum: an electronic drum pad may be able to replay a single sound at variable volumes when struck by a performer, but an acoustic drum produces infinitely variable sounds depending on how, where and with what the drum is struck.
Further, current digital instruments and environments are not capable of listening to its users and responding in musically meaningful ways. For instance, a sequencer is capable of being programmed to play back melodies, harmonies and shifting tonalities in time, however, it may not be capable of listening to another musician playing along with it and respond to that musician's intent to change tempo, chords, or tonality in real time.
There is a need for a system that can emulate and synthesize percussion instruments without losing the benefits of the acoustic and analog nature of the original instrument. There is a further need for such a system that can interpret signals captured from such percussion instruments and utilize them to control the output of a computer system. There is a further need for such a system that is adaptable to equipment that percussionists use currently and are comfortable with without the limitations of traditional microphones.
There is a further need for a platform in which the system described may be trained to better recognize signals captured, as well as a platform in which musical information can be extracted from audio data streams acquired elsewhere.
Finally, there is a need for a system that has the capability of interpreting its input as musically relevant information in order to follow, play along with and support other musicians.